Improvement in furnaces for assaying



T M'me.

-FURNACES FOR ASSAYING.

Patented Aug. 22,1876-,

Zal/? Wfizmses N. PETERS, FHOTO-LITHOGRAPHER, WASHINGTON, D C.

* UNITED!l [PATENT OFFICE.,

'rnnonon Benen, on New YORK, NQY.

IMPROVEMENT-IN FURNCES FOR ASSAYING.

Specification forming part ofV Letters Patent No. 181,304, dated August22, 1876; application filed y March I, 1876.

To all whom it may concern:

Be it known that I, THEoDoR M. BERGE, of New York city,have invented anImproved Furnace for Assaying, Enameling, and for other purposes, ofwhich the following is a specification:

My invention consists of a contrivance of' devices for enabling theemployment of interchangeable mufdes in assay and other like fur'-naces, in order that the capacity of the mutfle may be suited to therequirements of the case in hand at all times, thus making the furnacebetter adapted for varying quantities, conditions, and kinds of work,and securing greater accuracy. v

My invention also consists of an arrangement of the opening for theescape of' the gaseous substances, in such manner that the coal-dust andother impurities will be effectually prevented from falling into themufile, as they-do in the common arrangement, by which the assay is lessperfect and accurate.

Figure l is a sectional elevation of my improved furnace, taken on linea a, Fig. 2. Fig. 2 is a section on line b b, Fig. l. Fig. 3 is ahorizontal section. Fig. 4 is a side elevation and section of aremovable mouth-piece for using di'erent ones to suit mufdes ofdifferent sizes. v l

The furnace is designed to be portable, and to that end is constructedof fire-clay inner walls A and metal outer walls B, built on a suitablebase, G,for standing on the oor,and adapted for moving the furnace fromplace to place. D is a removable cover; E and F, doors; Gr, grate; H,ash-pit, and I smokepipe. J represents the muffle, in which the metalsand other substances to be treated are placed. It extends across thefurnace, and rests on a ledge, X, of the front and back wall, so as tobe readily put in and taken out for changing when different sizes arerequired. K is a removable mouth-piece to the opening in the front wallfor the mule. It is made removable for employing different ones adaptedto the muffies of different sizes. It closes around the top and sidesof' the mufde by its ntch L in the lower end, being dropped down from.the opening of door E in the dovetail notch M of the re-brick wall.The, ledge N closes around door F. The notch L of each mouthpiece willbe fitted to the particular muile with which it is to be used. A

To 4fit the diEerent sizes in the back wall, it is constructed with aledge,.O, to it the largest sizes, and another ledge, P, for the nextsize, and the mufes of smaller sizes are provided with a flange, Q, tofit theledge P. Thus, I secure tight joints at the ends of the removablemufes of different sizes without difficulty or delay when changing them.

H'eretofore the opening R for the escape of the gaseous products of theassay has been made in the top ofthe muffle, and the iiue S, forconveying them off, has been arranged directly over it, so that ashesand other matters have dropped `from the flue I into the muffle, andmingled with the metals and other substances under treatment to theinjury of the same, and making the assay inaccurate, I therefore makethe said passage horizontal inf the end of the muffle, and extend theflue S below it sufficiently to receive and retain the droppings.

In order that the heat may be cooled oft' as soon as possible after ithas done its work, so as to economize time, I `have the grate arrangedon projecting lugs T of the bottom plate U for its support, and have anotch, W, in it, which, being turned tothe adjacent lug T, lets thegrate, together with the fire, fall in to the ash-pit-for being drawnout quickly. The cooling of the furnaceV is also facilitated by the.walls being surrounded by the atmosphere.

The advantage of having muffles always adapted in size and capacity tothe work in hand is very important, as will be apparent to the skilledassayer for various reasons, besides the wider range of uses for whichit adapts the furnace.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-

1. An assaying-furnace having the front and back walls constructed andarranged to Stantilly as dscl'ibed.

2. The mufle J, having a flange, Q, in comes, substantiallyasdescvibedl.,

3. The mue having the escape-passage R` THEO.` M. BERGE.

In prsence of- WMaLKVEAew WWK;

AUGUSTUS VAN WYCK.

